Hybrid Radio Detector Triggering for Low-Power Tag Discovery

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing IoT devices face challenges with high power consumption during transceiver operations, making it impractical to power them using energy harvesting, especially in applications requiring global tag discovery and identification, and existing backscatter communication technologies have limited link budgets and are not suitable for cellular technologies like 5G NR.

Innovation Solution

A hybrid reader system with two passive energy harvesting modules and an active module that determines frequency range occupancy using power spectral density thresholds to trigger the active module only when necessary, allowing for efficient detection of backscatter signals and tag identification in unlicensed spectra.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If active radio detectors are continuously activated for tag discovery and identification, then detection capability is improved, but power consumption increases making energy harvesting impractical

Engineering Contradiction:
Improvedetection capabilityVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The system employs periodic sensing operations where passive modules periodically monitor frequency ranges and actively trigger the active radio detector only when occupancy conditions are met, rather than continuous operation. This periodic activation pattern significantly reduces power consumption while maintaining reliable detection capability.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

Passive energy harvesting modules autonomously monitor their respective frequency ranges and self-trigger the active radio detector when tag signals are detected, eliminating the need for continuous external power supply and control. The system serves itself by using harvested energy to intelligently activate detection only when needed.

Inventive Principle:
Principle #25Self-service

2Measurement precision

If passive modules monitor multiple frequency ranges with different bandwidths, then detection accuracy is improved, but system complexity increases

Engineering Contradiction:
Improvedetection accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The frequency spectrum is segmented into multiple distinct ranges, each monitored by a dedicated passive module with optimized bandwidth. The first passive module monitors a first frequency range with first bandwidth, while the second passive module monitors a second frequency range with second bandwidth. This segmentation allows each module to be simpler while collectively achieving high detection accuracy across the full spectrum.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Each passive module is designed with multi-functionality to perform both energy harvesting and occupancy detection of its assigned frequency range. The modules universally handle signal monitoring, power harvesting, and trigger generation, reducing overall system complexity by consolidating functions rather than requiring separate dedicated components for each task.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach reduces unnecessary activation of energy-hungry active radio detectors, enables efficient energy harvesting, and supports global tag discovery and identification, even in limited power conditions, while minimizing complexity and cost.

Implementation Method 1

The first passive module may comprise a first energy harvesting module. The first passive module may not have any other source of electrical power. The second passive module may comprise a second energy harvesting module. The second passive module may not have any other source of electrical power.

Methodology Applied
Scientific EffectEnergy harvesting: Electromagnetic Induction

Implementation Method 2

determining whether a power level (e.g. power spectral density (PSD)) of a received signal in each of the first plurality of frequency ranges is above a first threshold level, such that the respective frequency range is determined to be occupied

Methodology Applied
Scientific EffectPower spectral density detection:

Implementation Method 3

the active module comprises a radio detector for detecting a target waveform (such as an envelope detector based tag ID)

Methodology Applied
Scientific EffectBackscatter detection: Reflection

Data Source

PatentEP4307569A1Radio detector
Publication Date: 2024.01.17 NOKIA TECHNOLOGIES OY
  • EP4307569A1 patent drawingFigure 1~2
  • EP4307569A1 patent drawingFigure 3~4
  • EP4307569A1 patent drawingFigure 5~6

AI summary

An apparatus, method and computer program is described comprising: determining, using a first passive module, whether one or more of a first plurality of frequency ranges is occupied, wherein each of the first plurality of frequency ranges has one of a first set of one or more bandwidths; determining, using a second passive module, whether one or more of a second plurality of frequency ranges is occupied, wherein each of the second plurality of frequency ranges has one of a second set of one or more bandwidths, and wherein a smallest bandwidth amongst the second set of bandwidths is larger than a largest bandwidth amongst the first set of bandwidths; and triggering an active module in the event that one or more of the first plurality of frequency ranges is determined to be occupied and none of said second plurality of frequency ranges is determined to be occupied, wherein the active module comprises a radio detector for detecting a target waveform.